1. Field of the Invention
,The present invention is related to a diving mask with a soft nose projection and a drain mechanism. The mask also facilitates "balancing pressure" when diving.
2. Description of the Prior Art
A diving mask is one piece of equipment necessary for a diver. The mask helps the diver see clearly in the water, and protects the diver's eyes.
The soft lining frame of the diving mask is generally made of soft rubber so as to tightly and closely contact the diver's face. However, people's facial patterns differ from one another. Therefore, the diving mask cannot completely and closely contact all diver's faces, so water will enter the diving mask through a portion without a close contact between the mask and the face. When too much water is accumulated in the mask, the diver's breathing and vision will be seriously affected. Accordingly the accumulated water must be drained from time to time.
Therefore, a diver has to learn how to drain his mask before diving, particularly if he is diving with a "water lung" (deep water diving). If no drain valve is provided in the diving mask, the diver has to use his hand to press the upper edge of the diving mask, pull open the lower edge of the mask, and blow out any accumulated water by means of a nasal exhalation. However, such a draining procedure is inconvenient, and the diver has to be skillful, so beginners or unskilled divers may panic while attempting to drains their masks. If the diving mask is provided with a drain valve, the diver can directly blow out the accumulated water in the mask from the drain valve through his nasal exhalation. This construction is more convenient.
In addition, when diving with a water lung, in order to stay in the water for a long time, the diver is normally equipped with a water lung air cylinder (oxygen cylinder), and can breathe the air from the oxygen cylinder (which is a mixture of about 79% nitrogen and 21% oxygen), by cylinder. If there is no drain valve provided in the diving mask, the diver proceeds with exhalation and inhalation through his mouth. This can lead to a failure to entirely exhaust the nitrogen, and can cause nitrogen poisoning (i.e. the so-called nitrogen drunkenness which is similar to liquor drunkenness in that it can cause a disoriented state). If the diver is submerged long enough, and the diver's breathing only through his mouth can also cause his throat to become very dry and uncomfortable. However, the diving mask is provided with a drain valve, the diver can proceed with a self-regulated procedure of natural breathing through inhalation through mouth and exhalation (and drain) with his nose. Then the passage of his exhalation differs from that of his inhalation, and both his inhalation and exhalation are very smooth and comfortable. Also, nitrogen will not tend to accumulate in the diver's body, so that the diver will not be subject to nitrogen drunkenness.
In addition, when diving with the water lungs, because the water pressure at one depth differs from that of another depth )the deeper the water, the higher the water pressure), the diver needs to "balance pressure" when he changes depth. If he does not, the higher water pressure will lead to discomfort in the diver's ears, such as tinnitus. The so-called "balancing pressure" done to prevent the gradually increasing water pressure from disturbing the diver's ears in the course of his descent. The operation of "balancing pressure" is as follows: Prior to diving down to another depth, the diver first tightly shuts his mouth and holds his nose tightly shut with his fingers then exhales; the pressure will go to his ears to resist the increasing water pressure and the diver release his fingers from holding his nose after he reaches his desired depth.
At present, diving masks may be divided into two general categories: hard nose projection diving masks and soft nose projection diving masks. The hard nose projection diving mask (a) is shown in FIGS. 1 and 2. It is monocular and comprises a goggle frame (11), a soft lining frame (12) and a fixed frame: a soft lining frame (12) is nested in the inner flange (15) of fixed frame (13) through the frame rim (14). The goggle frame (11) is applied over the fixed frame (13), and both the goggle frame (11) and the inner flange (15) of the fixed frame (13) jointly hold the frame rim of the soft lining frame (12). The two sides of the fixed frame (13) can be provided with a head belt to affix the diving mask on the diver's head. The goggle frame (11) is designed to install a monocular glass (16) and integrally molded with a nose projection body (17) which is a hard nose projection made of the same material as that of the goggle frame (11). A valve hole can be conveniently provided in a suitable position (normally at the bottom of the nose) to form a valve seat for holding a valve diaphragm and to form a drain valve which opens outward unidirectionally to allow the water accumulated in the diving mask to drain outward from within, but to prevent water from seeping into the diving mask through the drain valve. Two nose-holding recesses (18) which are slanted inward are formed at the bottom of soft-lining frame (12) correspond to the positions of the nostrils of the diver. This allows the diver to close his nose to "balance pressure".
The soft nose projection diving mask has two types: monocular and binocular (the binocular type can be equipped with a binocular lens to accommodate nearsighted diver). The soft nose projection diving mask (B) as shown in FIGS. 3 and 4 comprises a goggle frame (2), a soft lining frame (3), two lenses (4), (4) and two fixed hoops (41), (41). The soft lining frame (3) has two separate frame rims (31), (31), a nose projection body (32) made of the same material as that of the soft lining frame (3). Lenses (4), (4) are mounted between the rims (31), (31) and the two separate inner flanges (21), (21) of goggle frame (2). The two sides of the goggle frame (2) may be provided with a head belt for affixing the diving mask to the diver's head.
Through a comparison of the advantages and disadvantages of hard and soft nose projection diving masks, it can be seen that the advantages of the hard nose projection diving mask consist in the direct disposition of a drain valve for convenient draining. the disadvantages thereof consist in (1) During the operation of "balancing pressure", the diver cannot hold his nose directly with his fingers because the nose projection body is hard. Further, the regulator in his mouth is an obstacle. The diver has to first bend his hand and then extend his hand upward into the interior of the nose-holding recesses of the soft lining so that he can hold his nose, making the operation of "balancing pressure" very inconvenient: (2) During the operation of "balancing pressure", the diver uses two index fingers of his two hand to extend upward into the interior to hold his nose as mentioned above, but if the diver holds other appliances such as a spear in his hand, he must hold the appliance in his armpit or between his legs to free his two hands; and (3) the lens is monocular and unable to accommodate the nearsighted diver.
So far as the soft nose projection diving mask is concerned, the advantages thereof consist in that due to the soft nose projection body, during the operation of "balancing pressure", the diver can directly hold the soft nose projection body from without. He can use a thumb and an index finger of one hand to close his nose, so that the operation of "balancing pressure" is very simple, quick, and convenient. A nearsighted diver can also choose a binocular lenses. However, the disadvantages thereof consist in the soft nose projection body having an unstable base. It can therefore not directly support a drain valve. Manufacturers in the past have never though of disposing a drain valve on the soft nose projection body, and no soft nose projection diving mask with a drain valve has never appeared in the market.